Abstract Extensive research suggests that components of the natural environment have profound effects on human health. In particular, individuals living in areas of low pollution and high levels of vegetation have been reported to have a lower burden of cardiovascular disease (CVD). Although many studies have shown that exposure to air pollution increases CVD risk and mortality, the impact of greenspaces and vegetation on CVD has not been directly studied. Hence to assess the impact of greenery on cardiovascular health and disease risk, we will conduct a pragmatic, interventional trial designed to test the hypothesis that exposure to neighborhood greenspaces diminishes CVD risk by decreasing the levels of local air pollution. To test this hypothesis, we will first evaluate baseline cardiovascular health in 16 residential neighborhood clusters with sparse greenspaces (Aim 1). In these areas, we will measure the levels of greenery, air pollution, noise and traffic, and determine how these neighborhood characteristics are associated with hospital admissions, as well as cardiovascular and all-cause mortality. To acquire individual level data, we will recruit 700 area residents and assess their cardiovascular health as well as psychosocial stress. Then, in 8 ?target? clusters, we will plant nearly 8,000 established trees (Aim 2). There will be no deliberate change in greenspace in the 8 ?control? clusters. Following the greening intervention, we will determine how an increase in greenspaces within the target clusters affects air pollution levels, hospital admissions and mortality, and how the greening intervention affects CVD risk and psychosocial stress within this community in comparison with the control area (Aim 3). Completion of this project would provide a new understanding of the link between urban greenspaces and cardiovascular health, and might lead to the development of new strategies to prevent CVD and to decrease the levels of urban air pollution. Importantly, the results of the project will lead to the development of a comprehensive model that could be readily adopted by cities throughout the world to create urban environments that are more conducive to human health.